The invention relates to a method for storing coils of wound band-like blank material and for charging a processing machine with said coils.
A method of this type is essentially described in EP-A-0 166 895. In this method, the coils (this name is used for rolls of steel or nonferrous metal bands) are stored in a horizontal position, i.e. with a vertical winding axis, in cassettes which contain supporting rolls for the coil. For processing, the cassettes are removed from the magazine and hoisted on a winch which has a horizontal axis and which requires an expanding means in order to hold the coil under tension from inside.
This EP-A-0 166 895 is primarily concerned with obtaining an ordered store so that any desired coil can be found rapidly at any time and fed to the unwinding station. Systems having roll arrangements in cassettes similar to that according to EP-A-0 166 895 which are used at the unwinding station have already been launched on the market. However, none of these roll arrangements ensures an even underlay for the coil, so that the known proposals all have handling and/or design disadvantages to which far too little attention has been paid so far with regard to optimizing the procedure. Because of the unstable support of the coil, the latter tends to collapse, in particular when it only has a few turns. If it is to be returned to the magazine, the individual windings have to be tied up at several points in order to prevent the band from becoming entangled. For the same reason, however, the expandable winch, which is expensive to construct and is also known from the textile industry for handling hanks, is also required, but in this case must be of much more massive construction so that the unstable coil does not fall apart, particularly in the vertical position, i.e. when the axis is horizontal. Nevertheless, this cannot be completely avoided in the case of the known proposals, which may lead to spoilage owing to distortion of the material. To date, all these disadvantages have been accepted as unavoidable.